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Message-ID: <4f90ea32-4d18-dcf7-0ca1-586f7e6c8043@quicinc.com>
Date:   Thu, 18 Aug 2022 10:25:25 +0800
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Subject: Re: [PATCH v8] mm/page_owner.c: add llseek for page_owner
To:     Andrew Morton <akpm@linux-foundation.org>
CC:     <vbabka@kernel.org>, <minchan@kernel.org>, <vbabka@suse.cz>,
        <iamjoonsoo.kim@lge.com>, <linux-kernel@vger.kernel.org>,
        <linux-mm@kvack.org>
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 <20220817091324.59afdb143b6330974f4e9e4c@linux-foundation.org>
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From:   Kassey Li <quic_yingangl@quicinc.com>
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On 8/18/2022 12:13 AM, Andrew Morton wrote:
> On Tue, 16 Aug 2022 10:07:48 +0800 Kassey Li <quic_yingangl@quicinc.com> wrote:
> 
>> There is usage to dump a given cma region page_owner
>> instead of all page's.
> 
> So... dump all the pages and then parse out the ones you're interested in?
> 
> Presumably this is too slow and presumably you have a use case in which
> this operation needs speeding up?  If so, please fully describe all of
> this in the changelog.  If not then please fully still describe the
> reasons for making this change.
> 
that is correct, I will update the change log for detail make it easy to 
know why we need this change.